diff --git a/README.md b/README.md
index 89af9ab..acb8c26 100644
--- a/README.md
+++ b/README.md
@@ -23,14 +23,15 @@ CapabilityEcho does **not** scan agent config files such as `.mcp.json` or `.cla
 
 ## Part of an AI-agent governance suite
 
-Four tools mapping orthogonal failure modes of AI-agent deployment:
+Five tools mapping orthogonal failure modes of AI-agent deployment:
 
 - **[ScopeTrail](https://github.com/Conalh/ScopeTrail)** — config drift over time (PR-level).
 - **[PolicyMesh](https://github.com/Conalh/PolicyMesh)** — policy contradictions across agent surfaces.
 - **CapabilityEcho** *(this repo)* — capability drift via code, not config.
 - **[TaskBound](https://github.com/Conalh/TaskBound)** — scope creep after the agent runs.
+- **[SessionTrail](https://github.com/Conalh/SessionTrail)** — runtime behavior review across agent session transcripts.
 
-The first three are preventive (static analysis of config and code). TaskBound is detective (behavioral, comparing stated intent vs. actual diff).
+ScopeTrail, PolicyMesh, and CapabilityEcho are preventive (static analysis of config and code). SessionTrail is runtime (in-session transcript review). TaskBound is detective (stated task vs. actual diff).
 
 ## Demo